M&S Uniform Girls' Culottes stink - literally...

I'm new to the school uniform rodeo, DD starts reception next month and I ordered her the M&S culottes with 'triple-action stormwear'. When I opened the package it smelled very faintly of... cat wee. If you'v ever had a cat, you know how sometimes you walk into a room and you think, that cat has done a wee somewhere - that's what it smells like when you walk past these shorts. I've washed them a few times and it's starting to fade a bit but I don't want to send my daughter to school smelling like the vet's waiting room.

Is this anything to do with the coating they use on school uniforms? Has anyone else had this happen?

Bought DS asda school trousers. They have this odd smell too. Only realised it was the trousers yesterday when ironing all the school things. I've been pestering D's for two weeks asking if he's hid wet clothes from me .

I am having exactly the same problem with some girls school trousers I bought a couple of weeks ago. I have washed them several times, soaked them in fabric conditioner, then I tried Napisan (as in the stuff you use to wash cloth nappies!) nothing works. The zip area stinks like cat wee. It's driving me crazy.